In the course of reading a radiological exam, radiologists can make annotations on an image using a computer workstation. For example, an annotation can be added to an image to visualize a measurement of a particular object represented by the image, or point to a particular structure of interest. For example, the annotations can comprise symbols, such as arrows or other symbols, and/or text strings.
For example, the annotations may be superimposed on the digital image and stored together with the image as a bitmap. Alternatively, the annotations may be stored as separate digital objects together with the original image; for example, as a presentation state. A snapshot of an annotated image may be stored in a radiology report document, for example.
WO 2004/057439 (A2) describes a method and system for visually annotating an image. It is said that annotations and notes to images, such as digital medical and healthcare images, may be stored in a structured vector representation alongside image information in a single, non-volatile and portable file or in a separate file from the image. The annotations may be composed of point, line and polygon drawings and text symbols, labels or definitions and captions or descriptions. The annotations may be structured in a manner that facilitates grouping and manipulation as user defined groups.